Control device having temperature responsive means for regulating the pressure regulator thereof



Feb. 15, 1966 M. J. CAPARONE ETAL CONTROL DEVICE HAVING TEMPERATURERESPONSIVE MEANS FOR REGULATING THE PRESSURE REGULATOR THEREOF Filed May23, 1962 4 Sheets-Sheet l INVENTORS MICHAEL J. CAPARONE HUBERT A. RICHTHEIR ATTORNEY I 1966 M J. CAPARONE ETAL 3,235,179

CONTROL DEVICE HAVING TEMPERATURE RESPONS'IVE MEANS FOR REGULAI'ING THEPRESSURE REGULATOR THEREOF Filed May 23, 1962 4 sheetsesheet 2 T 4/? a 0if 36 L35 f X3 1 34 i M 38 *t 4% if {6 r 2% g. 4 4! iNvEmoRs MICHAEL J.GAPARONE HUBERT A. RICH THEIR ATTORNEY 1966 M. J. CAPARONE ETAL 3,

CONTROL DEVICE HAVING TEMPERATURE RESPONSIVE MEANS FOR REGULATING THEPRESSURE REGULATOR THEREOF Filed May 25, 1962 4 Sheets-Sheet 5 I {I4 I774 Z0. J

FIG]

F 6 I-NVENTORS MICHAEL J.CAPARONE HUBERT A.RICH

Feb. 15, 1966 M. J. CAPARONE ETAE. 3,235,179

CONTROL DEVICE HAVING TEMPERATURE RESH,=['ISIVE MEANS FOR REGULATING THEPRESSURE REGULATOR THEREOF Filed May 23. 1962 4 Sheets-Sheet 4 7 53A y4-5% 4 ll 75 40bi- 100- w m1 103 77 [2 Z mvemoRs MICHAEL J.CAPARONE HUBERTA. RICH THEIR ATTORNEY United States Patent CONTROL DEVICE HAVINGTEMPERATURE RE- SPONSIVE MEANS FOR REGULATIN G THE PRESSURE REGULATORTHEREOF Michael John Caparone, Arcadia, and Hubert Allen Rich,Westminster, Calif., assignors to Robertshaw Controls Company, Richmond,Va., a corporation of Delaware Filed May 23, 1962, Ser. No. 197,077 9Claims. (Cl. 236-33) This invention relates to improved control devicesfor providing variable recovery rates for an appliance or the like.

More specifically, this invention relates to control devices for hotWater supply tanks and the like wherein the control device varies thepressure of the fuel delivered to a burner means for the hot Watersupply tank in response to the temperature of the water in the supplytank.

Heretofore, control devices for controlling the flow of fuel to theburner means of hot water supply tanks have been controlled by manualand thermostatic operations wherein a temperature sensing means isdisposed in the hot water supply tank and intermittently operates avalve means which controls the flow of fuel to the burner means tomaintain the water in the supply tank at a desired temperature.

However, during certain periods of the day when there is a large demandand a correspondingly large drawolf of hot water from the supply tank,the burner cannot restore the temperature of the water in the tank tothe desired value with suflicient rapidity whereby subsequent draws ofWater are made with water below the desired temperature. I

To attempt to avoid this situation, it has been necessary to set thecontrol point temperature of the temperature sensing meansat a highervalue whereby the supply tank is subjected to higher water temperaturesthat greatly decrease the life of the supply tank.

According to the teachings of this invention, however, an improvedcontrol device is provided which will operate the burner means of thehot water supply tank at normal recovery rates during normal use of thesupply tank and will automatically increase the recovery rate whenexcessive demands are made on the supply tank without subjecting thesupply tank to adverse temperatures that would tend to shorten the lifeof the tank.

In addition, the control device of this invention can be so constructedand arranged that the control device prevents the temperature of thewater in the supply tank from overshooting the selected temperature asin prior known devices.

Therefore, it is an object of this invention to provide an improvedcontrol device having one or more of the novel features set forth'aboveor hereinafter shown or described.

Other objects, uses and advantages of this invention are apparent from areading of this description which proceeds with reference to theaccompanying drawings forming a part thereof and wherein:

FIGURE 1 is a fragmentary, schematic view illustrating one applicationof the improved control device of this invention.

FIGURE 2 is an enlarged fragmentary, partial crosssectional view takensubstantially on line 2-2 of FIG- UREl.

FIGURE 3 is an enlarged, fragmentary, broken-away view takensubstantially in the direction of line 3-3 of FIGURE 1.

FIGURE 4 is a fragmentary side view taken in the direction of line 4-4of FIGURE 3.

FIGURE 5 is a fragmentary view taken in the direction of line 5-5 ofFIGURE 3.

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FIGURE 6 is an enlarged, cross-sectional view of the temperature sensingmeans illustrated in FIGURE 3 and is taken on line 6-6 thereof.

FIGURE 7 is a view similar to FIGURE 3 illustrating another embodimentof this invention.

FIGURE 8 is a fragmentary view similar to FIG- URE 7 and illustratesstill another embodiment of this invention.

FIGURE 9 is a cross-sectional view taken on line 9-9 of FIGURE 8.

While the various features of this invention are hereinafter describedand illustrated as being particularly adaptable for controlling theheating means of a. hot water supply tank or the like, it is to beunderstod that the various features of this invention can be utilizedsingly or in any combination thereof to provide other constructions asdesired.

Therefore, this invention is not to be limited to only the embodimentsillustrated in the drawings, because the drawings are merely utilized toillustrate one of the wide variety of uses of this invention.

Referring now to FIGURE 1, an improved system for heating water in a hotwater supply tank 10 is generally indicated by the reference numeral 11and'comprises an improved control device 12 of this invention adapted toregulate the flow of fuel to a burner means 13 for the hot water supplytank 10 in a manner hereinafter described to automatically provide anormal recovery rate when normal draws are made on the supply tank 10and to automatically increase the recovery rate when excessive draws aremade on the supply tank 10.

In addition, the control device 12 of this invention is adapted toprevent overshooting of the temperature of the water in the supply tank10 ina manner hereinafter described.

The control device 12 includes a housing 14 formed from a plurality ofparts in a manner hereinafter described and has an inlet 15 adapted tobe interconnected to a source of fuel by aconduit I6 and has an outlet17, FIGURE 2, adapted to be interconnected to a conduit 13 leading tothe burner means 13.

As illustrated in FIGURES 2 and 3, the housing 14 of the control device12 is formed from a plurality of parts 19, 2t), 21 and 22 suitablychambered and interconnected together, the part 22 comprising a shank ofa temperature sensing means 23 adapted to support the control device 12to the supply tank 10 in the manner illustrated in FIGURE 3 wherein theshank 22 has an externally threaded portion 24 threadedly received in anipple or bushing 25 secured in an aperture 26 in the wall 27 of thesupply tank 10 so that the temperature sensing means 23 can have aportion thereof disposed inside thesupply tank .10 andengageable by theWater contained therein for a purpose hereinafter described.

As illustrated in FIGURE 2, the control. device 12 has a gas cock valve28 adapted to be rotated by an externally mounted control knob 29 toselectively interconnect the inlet 15 with a chamber 30 formed in thehousing 14.

The chamber 369 in the housing 14 isseparated from another chamber 31formed in the housing 14 by an annular valve seat 32, the flow of fuelpassing from the chamber 30 to the chamber 31 being controlled by apressure regulator 33 of this invention.

The chamber 31 formed in the housing 14 is inter-- connected to theoutlet Why an annular valve seat 34, the annular valve seat 34 beingcontrolled by a valve member or means 35 normally urged to the closedposition by a compression spring 36.

While the particular details of the valve means 35 do not form a part ofthis invention, it will sufiice to state that the valve means 35 ismoved to an open position when a snap-action member 37 is snapped overcenter to engage sesame a stem 38 carried by the valve means and movethe stem 38 and valve means 35 to the left in opposition to the force ofthe compression spring 36.

For further information concerning the details and operation of thevalve means 35 and snap-action member 37, see the United States Patentto Jackson et al. No. 2,975,- 974, issued Mar. 21, 1961.

The snap-action member 37 is snapped over center when a plunger 39 ismoved to the left a predetermined distance.

A lever 40 is interconnected at one end thereof to the plunger,39 and atthe other end thereof to a fulcrumpositioning member 41 whereby theposition of the fulcrum member 41 is selectively adjusted by a controlknob 42 disposed within a detachable cover member 43.

The temperature sensing means 23 of this invention includes aconventional thermostat tube and rod arrangement wherein a tube 44,having a high coeflicient of ther mal expansion, has one end 44 thereofthreadcdly attached to the shank 22 so that the other free end of thetube 44 moves toward and away from the shank 22 depending upon thetemperature of the water sensed by the tube 44 expanding or contractingthe tube 44.

A rod 45 is disposed in the tube 44 and has the right end thereofsecured to the free end of the tube 44 in any suitable manner wherebythe left end 46 of the rod 45 is moved to the left upon a decrease intemperature in the supply tank 10 and is moved to the right upon anincrease in temperature in tank 10, the rod 45 having a relatively lowcoefficient of thermal expansion in relation to the tube 44 whereby thetube 44 and rod 45 form a bimetallic actuator.

The free end 46 of the rod 45 engages the lever 40 intermediate the endsthereof whereby movement of the rod 45 causes movement of the plunger 39of the snapaction member 37.

The control knob 42 of the control device 12 is so calibrated that thesame can select a desired temperature for the water in the hot watersupply tank It). For example, the control knob 42 can be disposed in aposition thereof to substantially maintain the water in the supply tank10 at approximately 155 F.

Depending upon the construction of the snap-action member 37 and thelever 40, the temperature sensing means 33 can cause opening of theValve means 35 upon a predetermined drop of temperature of the water inthe supply tank 10 below the selected temperature of 155 F. For example,the control device 12 can be so constructed and arranged that the valvemeans 35 will not be opened until the temperature of the water in thesupply tank 10 has dropped below 135 F. whereby the free end 46 of therod 45 has moved to the left a sufficient distance to cause thesnap-action member 37 to snap over center and open the valve means 35.

When the valve means 35 is opened in the above manner, fuel is adaptedto flow from a source thereof to the burner means 13 wherein automaticpilot means or the like ignites the same and the burning fuel tends toheat the water in the tank 10 to the selected temperature.

However, the snap-action member 37 is so constructed and arranged, thatthe valve means 35 does not close until the temperature-sensing means 23senses a temperature of 155 in the hot water supply tank 10.

The pressure-regulating means 33 of this invention is so constructed andarranged in a manner hereinafter described to tend to preventovershooting of the temperature in the water tank 10 should the burnermeans 13 be operated in the above manner.

Further, the pressure regulator 33 of this invention is so constructedand arranged that the same is adapted to provide a large recovery ratefor the system 11 should the temperature in the water tank 10 drop belowthe normal operation thereof because of excessive draws thereon in amanner hereinafter described. 4 As illustrated in FIGURE 2, the pressureregulator 33 comprises a flexible diaphragm 47 having its outerperiphery secured between the parts 15 and 20 of the housing 1.4, thediaphragm 47 carrying a valve member 48 cooperable to open and close thevalve seat 32 depending upon the position of the diaphragm 47 in amanner conventional in the art.

Alever 49 has one end 50 thereof bearing against the non-operating sideof the diaphragm 47 and has another end 51 thereof telescopicallydisposed and in sliding ongagement with a cylindrical boss 52 of thehousing 14 projecting into a suitably vented chamber 53 formed in thehousing 14.

The lever 42 is fulcrumed intermediate its ends 59 and 51 against afulcrum member 54, the end 51 of the lever 43 being urged to the left bya compression spring 55 disposed between the end 51 of the lever 49 anda collar 56 carried on a plunger 57.

Depending upon the position of the collar 56 of the plunger 57 relativeto the cylindrical boss 52, the force of the compression spring 55acting against the end 51 of the lever 49 determines the force tendingto move the valve member 48 of the pressure regulator 33 to an openposition thereof in opposition to the force of the pressure of the fuelin the chamber 31 acting against the diaphragm 47 to move the valvemember 48 to its closed position.

In this manner, by adjusting the force of the compression spring 55, bymoving the collar 56 relative to the cylindrical boss 52 in a mannerhereinafter described, the lever 49 and diaphragm 47 determines thepressure of the fuel passing from chamber 31 to the outlet 17 for apurpose hereinafter described.

A second temperature sensing means of this invention is generallyindicated by the reference numeral 58 in FIGURES 3 and 6 and comprises acylinder-defining mem-, ber 59 having a piston 61) disposed therein, thecylinder defining member 59 being filled with a temperature-sensingmedium 61, such as Wax or the like, whereby an increase in temperaturesensed by the temperature-sensing device 58 causes the wax 61 to expandand move the piston member 60 to the left. Conversely, a decrease intemperature sensed by the temperature-sensing means 58 causes thetemperature sensing medium 61 to contract whereby the piston 60 isadapted to move to the right.

While one type of temperature-sensing means 58 has been illustrated anddescribed above, it is to be understood that other types oftemperature-sensing means may be utilized as desire In the embodiment ofthe invention illustrated in FIG- URES 3-5, the temperature-sensingmeans 58 is mounted in a cavity 62 formed in the shank 22 of thetemperaturesensing means 23 at a point thereof disposed outside of thehot water supply tank 10.

However, since the water in the tank 10 engages the shank 22 of thetemperature-sensing means 23, the temperature of the shank 22 sensed bythe temperature-sensing means 53 is a function of the temperature of thewater in the tank 10 for a purpose hereinafter described.

As illustrated in FIGURES 3 and 5, an L-shaped lever 63, being definedby a pair of legs 64 and 65 disposed substantially at right anglesrelative to each other, has a pair of cars or lugs 66 carrying a pivotpin 67 having opposed ends disposed in s1ots68 formed in the housing 14and staked therein at 69 whereby the lever 63 is adapted to pivot aboutthe pivot pin 67.

The leg 64 of the levers 63 carries a pair of inwardly directed ears orlugs 70 adapted to engage the cylinderdefining member 59 of thetemperature-sensing means 53 when the lever 63 is rotated in a clockwisedirection under the force of a compression spring 71 disposed betweenthe leg 64 of the lever 63 and a retainer 72 secured to the housing 14by threaded fastening means 73. i

In this manner, an adjusting screw 74 is carried by the leg 64 of thelever 63 and is adapted to engage the piston 60 of thetemperature-sensing means 53.

Thus, u when thetemperature-sensing medium 61 of the temperaturesensing; device 58 contracts to permit the compression spring 71 topivot the lever 63 in a clockwise direction, the cars. 70 of the leg 64of the lever 63 limit. the degree of clockwisemovement of the lever 63as the same engage against the cylinder defining member 59 to preventfurther clockwise movement of the lever 63 even thoughthepiston 60. isadapted to be further moved to.the right upon further contracting of thetemperaturesensing medium. 61. r

The leg 650f. the lever 63 carries an adjusting screw 75 adapted toengage the upper end 76 of the plunger 57 previously described,

The lower. end\77 of the. plunger 57 is telescopically receivedfin. abore 78 formed. in the cylindrical boss 52 of the housing 14, whereby,movement of the plunger 57 is limited to axial movement thereof.

A compressionspring'79 is disposed inside the compression spring 75previously described, thecompression spring 79having one end thereofengaging the cylindrical boss 52 and the other endengagingthe collar56of the plunger 57 whereby the force of the compressionspring 79 tendsto move the collar 56 of the plunger 57 away from the cylindrical boss52to decrease the force of the compression spring 55 acting on the lever49 and, thus, lower the rate of fiow of fuel passing through thepressure regulator 33.

The amount of movement of the collar56 away from the cylindrical boss52is limited by an annular shoulder 80* of the plunger 57 engaging ahousing portion 81 through which the end 76 ofthe plunger 57 sealablyextends.

Therefore, it can be seen that as the temperature sensed by thetemperature-sensing means 58 of this invention increases, thetemperature-sensing medium 61 expands to move thepiston 60 to the leftin oppositionto the force of the compression spring 71 to tend to movethe lever 63 in a counterclockwise direction whereby the force of thecompression spring 79is adapted to move the plunger 57. away from thecylindrical boss 52 of the housing 14 to decrease the force of thecompression spring 55 and, thus, decrease the rate of flow of fuelthrough the pressure regulator 33.

Conversely, a decrease in the temperature sensed by thetemperature-sensing means 58 causes the temperaturesensingmedium 61 tocontract, whereby the force of the compression spring 71 is adapted tomove the lever 63 in a clockwise direction to cause the plunger 57 tomove toward the cylindrical boss 52 and increase the-force of thecompression spring 55, whereby the rate of flow of fuel through thepressure regulator 33 is increased.

Therefore, it can be seen that when the piston 60 of thetemperature-sensing means 58 has been moved to the left a distancesufficient to permit the annular shoulder 80 of the plunger 57 to abutagainst the housing 81 under the force of the compression spring 79, thepressure regulator 33 is set at its normal position to providea minimumflow offuel through the valve seat 32 of the pressure regulator 33.

Conversely, when the piston 60 of the temperaturesensing means 58 ismoved to the right to permit the ears 70 of the lever 63 to abut againstthe cylinder-defining member 59, the collar 56 of the plunger 57 ismoved theclosest to the cylindrical boss 52 ofthe housing 14, wherebythe pressure regulator 33;is.set at the maximum position thereof toprovide the maximum flow of fuel throughthe valve seat 3210f thepressure regulator 33;

The. operation of the control. device 12 will now be described; when itis: desired to have the temperaturesensing means 58prevent overshootingof the temperature of'thewater in the supplyrtank from the desiredtemperature thereof.

While certain dimensions and temperatures are hereinafter given inregard to the operation of the control devlcelZ, it is-to be understoodthat thesame are merely given by the way of. example ratherthanlimitetion.

First, assume that the control. knob 42v of the control device 12 is setsothat thevalve means 35 willclose when the temperature sensing means2-3sensesatemperaturelof 155 F. in the hotwater supply tank 10. Further,assume that the temperature-sensing,means 23 hasa temperature,differential of approximately 20 R, whiclrwill result in the valve means35 being snapped to. itsopen position when the temperature-sensing means23 sensesa temperature of approximately 135 F.

In addition, assume that, theshank temperature being sensed by thetemperature-sensing means 58 is apprQXimately. 15 F. to F. below thewater temperature in tank 10, such temperature differential beingdependent on heating rate, operating temperature, andj the like.

For this example, also assume that the temperaturesensing means 58 hasits maximum movement of the piston 60 occurring between 115 F. and? 135F., whereby the piston 60 is essentially contracted at 115" F,. fullyexpanded at, 135 F. and providing movement of the piston 60 ofapproximately 0.160 of an inch during such temperature range.

When hot water has been drawn from the supply tank It and replaced bycold water therein in a conventional manner to reduce the temperature ofthe water in the supply tank 10 to approximately 135 F;, thetemperaturesensing means 23 opens the valve means to interconnect thesource of fuel with the burner means 13 At this on temperature of thewater in the tank 10, the temperature-sensing means 58 of this inventionsenses a shank temperature of approximately 115 F., whe'reby the pistonwill be disposed in its fully contracted posi-/ tion to cause the tabsof the lever 63 to be in contact with the end of the cylinder-definingmember, 59, so that the collar 56. of the plunger 57 is disposed in itsclosest position to the cylindrical boss 52 of the housing 14 to causethe pressure regulator 33 to have a maximumflow of fuel to flowtherethrough to the burner 13 and, thus; provide a maximum recovery ratethereof.

Under this condition, a maximum outlet pressure adjustment is provided,delivering a relatively high orifice pressure to the water heater burnermeans 13, resulting in a relatively high recovery rate.

If it is desired to adjust the maximum outlet pressure provided by thelever 63' when the ears 70 are disposed against the end of thecylinder-defining member 59, the adjusting screw. can. be rotated intheproper direction to change the maximum setting of the. pressureregulator 33.

As the burner means 13 isoperatedin .theabove: mane ner to heat thewater in. the hot water supply tank. 10,v the valve means. 35 remainsopen, as the temperature of the water increasesmfrom 135 F; to 155 F..

However, asthe temperature. ofthew'ater in: the tanlc 10 increases from135 F. to 155 F., the temperature of: the shank 22 sensed by thetemperature-sensing. means 58 increasesfrom to; F., whereby the tem-.perature-sensing medium 61 expands tocause: the: piston: 60; to moveapproximately'0l160: of aninch to the left. This leftward m vement ofthe piston-160: causes thellev er. 63 to progressively move in; a:counterclockwise direc-: tion to progressively decrease'the force. ofthe compress sion spring 55 tending, to open the valve member 48; so;that the -r-ate;of flow of fuel throughthezpressure regula-. tor 33gradually reduced; from its maximumposition. to its minimum position asthe'temperature of thegwaterxint the water heater tank. 10*approaches F.

Thepoint at whichthe piston 60 of thetemp'enaturesensing means 58contacts the adjusting screw 74to-cause= such counterclockwise rotation.of. the lever. 63 is dependent upon the position of the. adjustingscrew.74.. relative to the ends ofthe cars 70.

Therefore, adjustment of the screw 74-,towards or away from the pistonGOdetermines the temperature atwhich the regulator pressure setting ofthe pressure regulator 33 starts to be lowered from its maximum value.

For example, setting of the adjusting screw 74 to contact the end of thepiston 60 of the temperature-sensing means 58 after an initial movementof the piston 60 of approximately 0.035 of an inch means that theinitial movement of the lever 33 occurs at a shank temperature ofapproximately 120 F which is equivalent to a water temperature ofapproximately 140 F The regulator pressure of the control device 12would therefore be at its maximum value when the water temperature inthe tank is at 140 F. or below, providing maximum recovery up to thispoint.

After the water temperature has risen above 140 F. and the shanktemperature has risen to above 120 F., the regulator pressure isprogressively reduced as the temperature-sensing medium 61 of thetemperature-sensing means 58 expands until, at a shank temperature ofapproximately 135 R, which occurs at a water temperature ofapproximately 155 F., the piston 60 is moved a total of approximately0.160 of an inch and has moved the upper arm 64 of the lever 63approximately 0.125 of an inch.

As the lever ratio of the lever 63 is 1 to 1 /2, this results in amovement of the plunger 57 of approximately 0.1875 of an inch.

This movement of the plunger 57 results in a reduction of the regulatedoutlet pressure from its maximum to a minimum when the water has reachedthe Off temperature setting of approximately 155 F. and provides aprogressively lower input of fuel to the burner means 13, as the Offtemperature is approached to thereby prevent overshoot of the Offtemperature of the water in the hot water supply tank 10.

The minimum setting of the pressure regulator 33 is restricted by theshoulder 80 of the plunger 57 abutting against the wall 81 of thehousing 13 should further counterclockwise movement of the lever 63 beeffected due to variations in the amount of movement of the piston 60 ofthe temperature-sensing means 58 or by variations in the settings of theadjusting screw 74. This additional travel of the lever 63 in acounterclockwise direction is taken up by the compression spring 71without additional travel of the plunger 57 and the adjusting screw canlose contact with the topend 76 of the plunger 57 under theseconditions.

Movement to increase the pressure setting of the pressure regulator 33is caused by the compression spring 71 overcoming the combined forces ofthe regulator spring 55 and the return spring 79.

Movement to decrease the regulated pressure setting of the pressureregulator 33 is caused by the temperaturesensing means 58 overcoming theforce of the compression spring 71 and causing movement of the lever 63in a counterclockwise direction to allow the return spring 7? to movethe plunger 57 upwardly, as shown in FIGURE 3, to thereby reduce theforce of the regulating spring 55 acting on the lever 49.

- While the temperature-sensing means 58 of this invention has just beendescribed as'operating during the normal use of the hot water supplytank to prevent overshooting of the temperature thereof as thetemperature approaches the OE temperature setting, it is to beunderstood thatthe temperature-sensing means 58 of this invention can beutilized in a manner to provide a maximum setting of thepressureregulator 33 only during abnormal uses of the supply tank 10caused byexcessive draws thereon over the normal draws encountered bythe supply tank 10.

' For example, the temperature-sensing means 58 can be calibrated insucha manner to actuate over a relatively lower range of temperatures, sothat in the normal range of the temperature differential of thetemperaturesensing means 23, the temperature-sensing means 58 is alwaysin an expanded condition, delivering "a 'pre-set normal or minimumoutlet pressure through the pressure regulator 33. 1

In the case of a severe draw of water on the supply tank 10, causing thewater temperature in the supply tank 10 to drop below the On point ofthe temperaturesensing means 23, the temperature-sensing means 58 wouldthen be in its operating range and as it is contracted, the'temperature-sensing means 58 would provide progressively higher outletpressure settings of the pressure regulator 33 until the pre-set maximumoutlet pressure thereof is reached.

In .this example, the control device 12 would provide a relativelyminimum or normal burner input when the water temperature range of thewater in the supply tank 10 remained within the temperature differentialrange of the temperature-sensing means 23.

' In the case of a high demand for hot water and a resultant drop inwater temperature in the tank 10, the regulated outlet pressure of thecontrol 12 wouldbe progressively increased to a pre-set maximum,resulting in a progressively increasing input and higher recovery rate.

Accordingly, it can be seen that the control device 12 of this inventionis adapted to vary the recovery rate of a burner means for a hot watersupply tank or the like by utilizing a temperature-sensing means sensingthe temperature of a part of the housing of the control device, the partof the housing having a temperature which is a function of thetemperature of the water in the supply tank and, in the embodimentillustrated in FlGURES 35, the part of the housing comprising part of atemperaturesensing means.

Another embodiment of this invention is generally indicated by thereference numeral 12a in FIGURE 7, wherein parts thereof similar to thecontrol device 12 are indicated by like reference numerals followed bythe reference letter a.

As illustrated in FIGURE 7, the control device 12a includes thetemperature-sensing means 23a, adapted to support the control device 12arelative to the wall 27a of the hot water supply tank 10a, the shankportion 22a of the temperature-sensing means 23a being received in abore 82 formed in an unthreaded nipple 83 secured in the aperture 26a ofthe supply tank 10a.

The control device 12a is further supported relative to the supply tank10a by a plate-like member 84 secured to the shank 22a in any suitablemanner and abutting against outwardly directed ears or lugs 85appropriately secured to the exterior surface of the wall 27a of thetank 10a and having threaded ends 86 passing through suitable bores inthe plate 84 and secured thereto by nuts 87.

The shank 22a of the control device 12a has a cavity 88 formed thereinto define an end wall 89 engageable by the water in the supply tank 10a.

The temperature-sensing means 58a is disposed in the cavity 88 and hasthe plunger or piston 60:: thereof adapted to abut the adjusting screw74a carried by one end 90 of a lever 91 pivotally mounted to the housing14a by a pivot pin 92, the adjusting screw 74a tending to be held incontact with the piston 60a by the compression spring 71a.

The other end 93 of the lever 91 carries an adjusting screw 75a adaptedto abut the upper end 7 6a of the plunger 57a, the plunger 57a varyingthe force of the compression spring 55a in the manner previouslydescribed in regard to the control device 12.

Therefore, it can be seen that in the embodiment illustrated in FIGURE7, the temperature-sensing means 58a senses the temperature of the shank22a at a portion thereof having a temperature similar to the temperatureof the water in the tank 10a, because merely the end wall 89 of theshank 22a separates the temperature-sensing device 58a from the water inthe tank 10a.

Another control device of this invention is illustrated in FIGURES 8 and9 and is generally indicated by the reference numerallZb, the partsofthe control device 12b that are similar to the parts of the controldevice 12 are in: dicated by like reference numerals followed a by thereference letterfbf As illustrated in FIGURE8, the:housing,,1 4b ofthecontrol; device, IZbyll'lOllldGS a temperature-sensing means 23bcomprising a. shank portion 22b threadedly, secured in the nipple 25bdisposed in-the-aperture 26b ofgthe wall 27b of the supply tank 10b. Inaddition, the temperature-sensing; means 23b, includes the, tube 44b,having the-end 44] thereof secured inthe shank 22b anda free end 94disposed-in the interior of. supply, tank 10b.

The free end 94 of the tube 44b is internally threaded at 95 to receivea threaded insert 96 threadedly carrying an end 97:? of the' rod bwhereby the end 97 of the rod 45b is connectedto the free end 94 of thetube 44b, so that the free end 46b of therod 45b is moved relative tothe housing 14b upon expansion and contraction of the tube 44b in'themanner previously described.

The temperature-sensing means 58b of the control device 12b iscarried-by the free end 94 of the tube 44b, the cylinder-defining member59b of the temperaturesensing means 58 b is exteriorlythreadedat 98- toattach the same-to the threads 95 ,ofthe tube 44b.

The piston 60b of the temperature-sensing means 58b engages a plate 99having a pair of depending legs 100 respectively passing through slots101 in the threaded insert96, so that the free ends 102.0fthe legs 100can abut: against an annular shoulder 103 of a tubular member 104telescopically disposed about the rod 45b.

The tubular member 104 has an annular flange 105 at the other endthereof adapted to engage an end 106 of a lever 107, the end 106 of thelever 107 being substantially U-shaped to surround part of the rod 45b,so that the lever 107 does not impede movement of the rod 45b.

The lever 107 is pivoted intermediate its ends 106 and 108 by a pivotpin 109 carried by the housing 14b, the end 108 of the lever 107carrying an adjusting screw 75b adapted to engage the upper end 76b ofthe plunger 57b utilized in a manner previously described to vary theforce of the compression spring b and, thus, to vary the setting of thepressure regulator of the control device 12b.

The adjusting screw 75b of the lever 107 is tended to be moved intoengagement with the upper end 76b of the plunger 57b by a compressionspring 71b disposed between the end 108 of the lever 107 and a retainer72b carried by the housing 14b.

Therefore, it can be seen that the temperature-sensing means 58b of thisinvention is engageable by the water in the tank 1%, whereby thetemperature-sensing means 58b not only senses the temperature of thewater in the tank 10b but also the temperature of the free end 94 of thetube 54b, which is disposed in the water in the tank 10b. In thismanner, the temperature-sensing means 58b, in effect, senses thetemperature of the temperaturesensing means of the control device 12b inmuch the same manner that the temperature-sensing means 58 and 58a ofthe other embodiments of this invention respectively sense thetemperature of the temperature-sensing means 23 and 23a.

In the operation of the control device 12b of this invention, it is tobe understood that the amount of movement of the piston member b of thetemperature-sensing means 58b far exceeds the amount of movement of thefree end 94 of the tube 4411 during the same change in temperature ofthe temperature-sensing means 58b and the tube 44b.

In this manner, even though the tube 44b is contracting due to adecrease in temperature of the water in the tank and tending to move thetemperature-sensing means 58b downwardly as illustrated in FIGURE 8 todecrease the pressure of the fuel flowing to the main burner means,

the piston 60b moves upwardly to a greaterextent to actually increasethe pressure of the fuel.

Conversely, when the temperature of the water in the tank 10b increasesthe free end 94 of the;tube,44b moves upwardly and-carries thetemperaturesensing means 58b therewith in: a direction tending toincrease the pressure of the fuel; Howeventhe piston, 60b of, thetempera Lure-sensing means 58b moves downwardly to a greater extent-t0actually decrease the, pressure of the fuel.

Therefore, even though; the temperature-sensing means 58b moves with thetu-be 44b, the temperature-sensing means 58b provides the;desiredpressuresetting variations throughout the entire operating range,of the control device12b.

Thus, itcan. be seen that this invention provides various. embodimentsof controldevices particularly adaptable for water heater systems andthe-like, wherein thereon: trol devices canbe utilized tovary the-rateof flow of fuel to the, burner means of the water heater, tanks inaccordance with the function of the temperature of the water in thetanks 10 to prevent overshooting, of, the Off temperaturesthereof, aswell as to provide high recovery rates when the temperature of thewaterin the tanks is below'a predeterminedtemperature and to provide normalon minimum flow of fuel to the burners when thetemperature of thewateris in the normal open ating temperature of the water inthe supplytanks.

While the form of the invention now preferred has beendisclosedasrequired by the; statutes, other forms may, be used, allcoming within the scope of the claims which follow.

What is claimed is:

1. A device for controlling the heating of a water tank or the like andcomprising a housing having an inlet adapted to be interconnected to asource of fuel and having an outlet adapted to be interconnected to aburner means for said water tank, a valve means disposed between saidinlet and said outlet to control the flow of fuel through said device, afirst temperature sensing means carried by said housing and operativelyinterconnected to said valve means to control said valve means inresponse to the temperature of said water in said tank, a pressureregulator carried by said device to control the pressure of the fuelflowing therethrough, and a second temperature sensing means operativelyinterconnected to said pressure regulator to control said pressureregulator in response to temperatures sensed by said second temperaturesensing means, said second temperature sensing means including a pistonand cylinder arrangement wherein said piston is moved relative to saidcylinder upon an increase in temperature, said second temperaturesensing means directly sensing the temperature of said first temperaturesensing means not the temperature of said tank or the water in saidtank.

2. A device for controlling the heating of a water tank or the like andcomprising a housing having an inlet adapted to be interconnected to asource of fuel and having an outlet adapted to be interconnected to aburner means for said water tank, a valve means disposed between saidinlet and said outlet to control the flow of fuel through said device, atemperature sensing means carried by said housing and operativelyinterconnected to said valve means to control said valve means inresponse to the temperature of said water in said tank, a pressureregulator carried by said device to control the pressure of the fuelflowing therethrough, and a second temperature sensing means carried bysaid first-named temperature sensing means and operativelyinterconnected to said pressure regulator to control said pressureregulator.

3. A device as set forth in claim 2 wherein said firstnamed temperaturesensing means has a portion thereof adapted to be disposed outside saidtank and said second temperature sensing means senses the temperature ofsaid portion of said first-named temperature sensing means.

4. A device as set forth in claim 2 wherein said firstnamed temperaturesensing means has a wall engageable by the water in said tank and saidsecond temperature sensing means senses the temperature of said wall ofsaid first-named temperature sensing means.

5. A device as set forth in claim 2 wherein said firstnarned temperaturesensing means has a portion adapted to be disposed in said tank and saidsecond temperature sensing means is carried by said portion of saidfirstna-med temperature sensing means and senses the temperature of saidwater.

6. A device for controlling the heating of a water tank or the like andcomprising a housing having an inlet adapted to'be interconnected to asource of fuel and having an outlet adapted to be interconnected to aburner means for said water tank, a valve means disposed between saidinlet and said outlet to control the flow of fuel through said device, afirst temperature sensing means carried by said housing and operativelyinterconnected to said valve means to control said valve means inresponse to the temperature of said Water in said tank, said firsttemperature sensing means including a shank portion adapted to heinterconnected to' said tank and a tube and rod arrangement carried bysaid shank portion, a pressure regulator carried by said device tocontrol the pressure of the fuel flowing therethrough, and a secondtemperature sensing means carried by said first temperature sensingmeans and operatively interconnected to said pressure regulator tocontrol said pressure regulator.

7. A device as set forth in claim 6 wherein said second temperaturesensing means senses the temperature of said shank portion at a pointoutside said tank. t

8. A device as set forth in claim 6 wherein said shank portion has awall engageable by the water in said tank and said second'temperaturesensing means senses the temperature of said wall of said shank portion.

9. A device as set forth in claim 6 wherein said tube has a portionthereof adapted to be disposed in said tank and said second temperaturesensing means is carried by said portion of said tube and senses thetemperature of said water.

References Cited by the Examiner UNITED STATES PATENTS 1,572,969 2/ 1926Schwimmer.

2,312,479 3/1943 Ray 23621 2,532,896. 12/1950 Dillman 23 699 2,664,24612/1953 Ray 23699 2,749,043 6/1956 Eskin 23621 2,784,913 3/1957 Wasson236-92 2,924,387 2/1960 Hajny 236-1 3,080,118 3/1963 McCarthy '236-32WILLIAM F. ODEA, Acting Primary Examiner.

ALDEN D. STEWART, EDWARD 1. MICHAEL,

Examiners.

1. A DEVICE FOR CONTROLLING THE HEATING OF A WATER TANK OR THE LIKE ANDCOMPRISING A HOUSING HAVING AN INLET ADAPTED TO BE INTERCONNECTED TO ASOURCE OF FUEL AND HAVING AN OUTLET ADAPTED TO BE INTERCONNECTED TO ABURNER MEANS FOR SAID WATER TANK, A VALVE MEANS DISPOSED BETWEEN SAIDINLET AND OUTLET TO CONTROL THE FLOW OF FUEL THROUGH SAID DEVICE, AFIRST TEMPERATURE SENSING MEANS CARRIED BY SAID HOUSING AND OPERATIVELYINTERCONNECTED TO SAID VALVE MEANS TO CONTROL SAID VALVE MEANS INRESPONSE TO THE TEMPERATURE OF SAID WATER IN SAID TANK, A PRESSUREREGULATOR CARRIED BY SAID DEVICE TO CONTROL THE PRESSURE OF THE FUELFLOWING THERETHROUGH, AND A SECOND TEMPERATURE SENSING MEANS OPERATIVELYINTERCONNECTED TO SAID PRESSURE REGULATOR TO CONTROL SAID PRESSUREREGULATOR IN RESPONSE TO TEMPERATURE SENSED BY SAID SECOND TEMPERATURESENSING MEANS, SAID SECOND TEMPERATURE SENSING MEANS INCLUDING A PISTONAND CYLINDER ARRANGEMENT WHEREIN SAID PISTON IS MOVED RELATIVE TO SAIDCYLINDER UPON AN INCREASE IN TEMPERATURE, SAID SECOND TEMPERATURESENSING MEANS DIRECTLY SENSING THE TEMPERATURE OF SAID FIRST TEMPERATURESENSING MEANS NOT THE TEMPERATURE OF SAID TANK OR THE WATER IN SAIDTANK.